Everyone knows viruses and trojans are bad, but a lot of people don’t know how exactly they work. Viruses, for example, are programs that copy themselves and infect a computer, spreading from one to another—just like, well, a real life virus. Trojans, on the other hand, are applications that look normal, but secretly have code that’s doing something else—like letting someone else control your computer. We highly recommend reading this explanation for more detail on the different types of malware, as well as the biggest myths surrounding them. And, as always, make sure you’re running a good antivirus program—even if you have good browsing habits.